Furnace



A. SMALLWOOD FURNACE 4 Sheets-Sheet 1 Filed Oct. 4, 1921 Oct. 6, 1925. 1,556,251

A. SMALLWOOD FURNACE Filed Oct. 4, 192] 4 Sheets-Sheet 2 l/l/III/II/IIIIIIII/III/II J Oct. 6, 1925- A. SMALLWOOD FURNACE Filed Oct. 4, 1921 4 Sheets-Sheet 3 A; SMALLWOOD FURNACE 4 Sheets-Sheet 4 Filed Oct. 4, 192] Patented Oct. 6, 1925.

UNITED STATES i ALFRED SMALLWOOD, or VHIGHGATE, ennon, ENGLAND.

FURNACE.

\ Application filed October 4, 1921. Serial No. 505,414.

To all whom it may concern:

Be it known that I, ALFRED SMALLwooD, a subject of the Kingdom of Great Britain, residing at 42, I-Iargrave Park, Highgate, London N, England, have invented certain new and useful Improvements in or Relating to Furnaces, of which a specification. I

' This invention comprises certain improvements in or relating to furnaces of the recuperator type, and ithas for various of its several purposes to increase the durability of the furnaces, and to increase its efficiency and utility.

According to the present invention, a recuperator system of the type having a passage or passages for waste gas located in proximity to a passage or passages for a fluid supply, such as air, sothat the waste gas is enabled to flow simultaneously with, and is isolated from, the air which it is adapted to heat, is so incorporated that at the will of the operator the air and waste gas passages may be interchanged in their functions, that is to say, the waste gas may be passed along the passage or passages which has or have conveyed air, and the air may be'conveyed along the passage or {passages which has .or have previously conveyed waste gases. This arrangement has the ad-,

1 vantage among'others that overheating-of the recuperator system can be avoided without loss of heat in the recuperator process;

' The present. invention furthermore com-C prehends the utilization, in combination with a'recuperator system of the type'abov'e defined haiving isolated Waste gas and air passages, of recuperator devices 'of the checkered brickwork or equivalent type through which the air and the waste'gas are adapted to" be passedalternately. 'By the interposi tion of recuperator devices of this checkered brick or equivalent type" between the source of supply ofthe waste gases andthe recuperator systemof the'isolated passage type, the latter is relieved from the'initiarl heat of the waste gases, this initial heatheing, nevertheless, utilized inthe recuperator Process f The invention may be adaptedgenerally to furnaces, and in one method of carrying out the invention, as applied, for instance, to a furnace of the reverberatory type, suitable for forging, melting, billet heating, or

' similar processes, I provide at each end or the following is side of the heating hearth or zone a waste gas outlet which may alternately function as a recuperated air inlet I'also provide at each end or side of this hearth a combustible gas inlet. 'The waste gas outlet may communicate with a checkered brickwork or PATENT OFFICE,

equivalent recuperator device through which the waste gas is enabled to flow, and after traversing this recuperator device the waste gas is admitted to alternate flues of acornmon recuperator device of the isolated passage type. The waste gases traverse the intermediate passages of this last-mentioned 'recuperator system and have egress therefrom by an appropriate flue or'flues to the stack, and the other or intermediate flues of thisisolated passage recuperator system are adapted to receive air which flows through the system and afterwards traverses a second of the, checkered brickwork or equivalent system, from which latter the air flows for admixture with the combustible gases for combustion at the working hearth.

The waste gas outlet from the isolated pas sage recuperator system and the air inlet f air inlet being at the same time placed in communication with the intermediate flues,

and ,by reversing the valve'those intermediate fines-may be adapted t0 conveyin a reverse direction thewaste gases, the air being then admitted to the other flues. According to the posif'tionof the reversing valve, therefore, the waste gas outlet on one side of'the furnace becomes an air inlet, and that on the other side of the furnace which has previously functioned as an air inlet becomes a waste gas outlet. A second reversing valve or system of valves is advantageously incorporated to admit the combustible gases to the appropriate side or working half of the furnace, and to shut off the supply of combustible gas to the other side of the hearth. This reversing valve may be coupled for'opera'tion electrically with the valve controlling the recuperator system. I

In crderthat this invention may be clearlOU ly understood and readily carried into practice, reference may be had to the appended explanatory drawings, upon which Figure 1 is a longitudinal section of a furnace according to the present invention.

Figure 2 is a section on line 22 of Figure 1.

Figure 3 is a sectional plan on line 3 3 of igure 1.

Figure 4 is a section through the chambers is, Z, Z hereinafter referred to.

Figure 5 is asection through the reversing valve 9 hereinafter referred to.

in a convenient embodiment of the present invention, a working hearth a is provided at each side with one or a series of gas inlets (5 which are in communication with a source of gas supply m (Figures 3 and 4). Situated on the outside ot the conduits which lead to the gas inlets a are fiues Z), which communicate with the hearth a at points above the gas inlets a The 'tlues Z2, situated on-either side of the hearth 1, are adapted to extend downwardly, and each communicates with a check red brickwork system 0. Situated below the hearth c0, and intermediate of the two checkered brickwork systems 0, is a recuperator system d, of the isolated passage type. The checkered brickwork systems 0, arranged on either side of the isolated passage recuperator (Z, are each adapted to communicate with one series of passages of therecuperator system (Z. Below the recuperator (Z are two flues f, 7, arranged in such a manner that one of the said flues is in communication with one of the sets of passages of the recuperator a, and the other flue is in con'imunication with the other set of passages ot the recuperator d. The ends of the tines and P, which are remote from he ends which communicates with the pas sages of the recuperators (Z, are adapted to communicate with a channel p, (Figure 5). Adapted to communicate with the said channel 2), are a second pair of lines 2' and 71, arranged opposite to each other, the flue "i being arranged in communication with the source of air supply, and the flue it being arranged in communication with the 'chimneystack;

Mounted in the channel 7 is a two-way valve 5/, which, in one position, provides for a communication between the air supply and the fine 7, and also a communication between the flue 7t and the flue 7. By rotating the said valve through the flue f is arranged in communication with the flue h, and the air supply i is arranged in connnunication with the flue f The gas air inlets a are adapted to communicate with fines Z. Z, which are adapted to receive supply of combustible gas from producers 7', j respectively, and the said fiues Z and Z are controlled by valves m and m and mounted upon a rocking arm n, so that when one valve is closed, the other is automatically opened. The valves m and m may be coupled to the valve 9 electrically whereby they are operated simultaneously.

Thus, it the valve 9 and the valves m and m are in the positions shown respectively in Figures at and 5, combustible gases will be passed through the flue Z and through the gas inlet a situated-on the right-hand side of Figure 1, and air will be passed through the flue f into one of the sets of isolated passages in the recuperator (Z, thence through the checkered brickwork systems 0 situated on the righthand side of Figure 1, through the flue Z), and issue in the hearth at a point just above the gas inlet a As the flue Z is shut by the valve m, no combustible gas will be allowed to proceed through the gas inlet a on the lefthand side of Figure 1, and the combustible gases formed in the hearth awill be passed through the flue b situated on the left-hand side of Figure 1, through the checkered brickwork systems 0 and the isolated passages of the recuperator (Z, and thence through the flue f to the chimney stack flue h.

The waste gases given oft by the hearth a will heat the incoming air passed through the isolated passages of the recuperator cl.

It will be observed that by actuating the valve 9 and the rocking arm a, the air and the combustible gases may be caused to flow through the air fines and gas inlets situated on the left-hand side of Figure 1, and the gas inlet a on the right-hand side of Figure 1 will then be closed, allowing the waste gases to pass through the flue 7) situated on the right-hand side of Figure 1, and thence through the checkered brickwork system 0 into the isolated passages of the recuperator cl, which, when the valve and rocking arm were in the other position, formed the passages for the air.

By the arrangement hereinbetore described, the advantage is obtained that the recuperator system cannot be overheated, and this function is obtained without in any way decreasing the temperature of the furnace.

Although in the specific construction described in relation to the accompanying drawings, one set of passages of the recuperator cl are in communication with {a source of air supply, nevertheless, it will be appreciated that this set of passages may be arranged in communication with a source of combustible gas supply, without in any way departing from the spirit of the invention, in which case the combustible gases would be pro-heated inthe recuperator cl. The entire recuperator system may, it desired, be duplicated in connection with the tors of the checkered brickwork type, and, in addition, if desired, the system will function over any desired period without it being necessary to reverse the process at all.

What I claim as my invention, and desire to secure by Letters Patent is 1. A furnace, which comprises, in combination, a hearth, a combustible gas inlet at each end of said hearth, and controlled to permit the admission of gas at one end only, flues located at each end of said hearth, and adjacent to the said gas inlets, a recuperator system built up of a plurality of passages, with every a'ternate passage arranged in communication and isolated from its neighbor to form two distinct sets of passages, which are arranged so that each communicates at one end with one of the sets of flues situated at one end of the hearth, means whereby a source of fluid may be arranged in communication with the end of the passage away from the hearth of one set of passages, and a chimney stack arranged in communication with the similar end of the other set of passages, and means whereby the said passages may be interchanged with relation to the source of fluid supply and the chimney stack, and means whereby the gas inlet which is situated adjacent to the flue which is in communication with the chimney stack, is maintained closed.

2. A furnace, which comprises, in combination, a hearth, a combustible gas inlet at each end of" said hearth, and controlled to permit the admission of gas at one end only, flues located at each end of said hearth and in adjacency to said gas inlets, two recuper'a-tor devices, comprising the equivalent of the checkered brickwork type, arranged so'that one communicates with the fines located at one end of the hearth, and the other 1 communicates with the flues situated at the other end of the hearth, a recuperator system built up of a plurality of passages, with every alternate passage arranged in communication and'isolated from its neighbor,

to form two distinct sets of passages which are arranged so that each communicates at one end with one of the said recuperator' devices, means whereby a source of fluid may be arranged in communication with the end of the passage away from the hearth of one set of passages, and a chimney stack arranged in communication with the similar jacent to that flue which is in communication with the chimney stack is maintained closed.

In witness whereof I have hereunto set my hand.

ALFRED SMALLWOOD. 

